Answer: 
Step-by-step explanation:
Let A = he known the answer then A' = he guess the answer.
B = he answered it correctly
As per given , we have



By Bayes theorem , we have

The probability that the student knows the answer given that he answered it correctly is
.
Hm so basically what the question is asking is
Answer:
-1,-1
Step-by-step explanation:
it is the midpint (-1,-1)
Answer:
2
Step-by-step explanation:
7+2n = 11
2n = 11-7
2n = 4
n = 4/2
therefore n = 2